Free Online Reverse Geocoding Web Service

https://geoservices.tamu.edu/Services/ReverseGeocoding/WebService/v04_01/SOAP/api.asmx

Parameter	Required	Description	Example	Possible Values
apiKey	true	click here for your API key	api-key-value	text string
version	true	the version of the parser to use	4.01	4.01
lat	true	the latitude of the input coordinate	34.0726207996348	double
lon	true	the longitude of the input coordinate	-118.397965182076	double
state	true	the abbreviation of the state of the input	CA	text string
geom	false	return the full geometry of the reference feature (creates a very large response)	true	true, false
includeHeader	false	include column headers for text (csv/tsv) output	true	true (include field headers) false (don't include field headers)
format	false	output format	csv	csv, tsv, xml, json
notStore	false	indicates if the transaction details should not be historically stored in your account	true	true, false

Position	Field	Required	Description	Possible Values
0	Query Status Code	true	Result code	See list
1	API Version	true	Vesion of the API used	4.01
2	Transaction Id	true	Query Id	Unique Id
3	Time Taken	true	Processing time	Milliseconds
4	Street Address	true	Closest street address to the input point
5	City	true	Closest city to the input point
6	State	true	Closest state to the input point
7	Zip	true	Closest ZIP Code to the input point
8	ZipPlus4	true	Closest ZIP+4 to the input point

Reverse Geocoding Web Service - SOAP API